Update accessibility action

Author: liamjberrisford

.github/workflows/accessibility.yml

@@ -1,7 +1,7 @@
 name: pa11y-accessibility-check
 
 on:
-  pull_request:
+  pull_request_target:
 
 jobs:
   accessibility_assessment_comment:
@@ -11,6 +11,7 @@ jobs:
     steps:
       - uses: actions/checkout@v3
         with:
+          ref: ${{ github.event.pull_request.head.sha }}
           fetch-depth: 0
 
       - name: Set up Python 3.11

home_page.md

@@ -13,4 +13,4 @@ You can contact the CfRR team at the following email: [codingforreproduciblerese
 
 Please register your interest in a particular course by completing the relevant form on the Workshop Schedule and Signup page available [here](cfrr_program_details/courses_overview.ipynb).
 
-For more details on the structure and use of this website, please go to ['How to use this website'](cfrr_program_details/how_to_use_CfRR.ipynb).
+For more details on the use of this website, please go to ['How to use this website'](cfrr_program_details/how_to_use_CfRR.ipynb).